The research is so designed that once _____ nothing can be done to change it.
| A．begins | B．having begun | C．beginning | D．begun |
We went right round to the west coast by __________ sea instead of driving across _________ continent.
| A．the … the | B．/ … the | C．the … / | D．/ … / |
Students should be encouraged to use ____Internet as ____resource.
| A．不填; a | B．不填; the | C．the; the | D．the; a |
Lucy's new job paid twice as much as she had madein the restaurant.
| A． | working | B． | work | C． | to work | D． | worked |
I bought a dress for you only 10 dollars in a sale; it was a real _____.
| A．exchange | B．bargain | C．trade | D．business |
Would it befor you to pick me up at four o'clock and take me to the airport?
| A． | free | B． | vacant | C． | handy | D． | convenient |